FAC Gravity

What it does

A frequency shifter aimed at barberpole and Shepard style glissandos, stereo rotation, chorusing, phasing and evolving echoes. Stereo mode shifts each channel independently with a ratio control for how closely the two align, while mono mode uses quadrature processing to widen a mono source. A spiral section feeds the shifter back through delay, blur and filtering, from gentle loops to analog self-oscillation. An LFO, envelope follower and modulation matrix can drive width, phase and pan.

In the demo

Jade starts on piano in AUM with the shifter untouched, raising only the spiral and blur so the feedback character is audible on its own. She then drives the shift from a MIDI keyboard, routes drums in over multibus to the envelope follower, and ends on a Field Kit soundscape with sync set to eight bars.

Worth knowing

It colours and moves everything it touches, so a static, transparent widener is not what this is doing. The limiter is worth leaving on, since the spiral runs into self-oscillation. The in-app purchases are a tip for the developer rather than an unlock.